LED lights???

Duke Mk1a

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I recently installed LED replacement bulbs (lights) for the park/brake lights. They work great and are bright as hell. My only issue is that the front white parking lights activate now when I hit the brakes.

Any idea how to stop this?
 

Moondoggie

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I recently installed LED replacement bulbs (lights) for the park/brake lights. They work great and are bright as hell. My only issue is that the front white parking lights activate now when I hit the brakes.

Any idea how to stop this?

Hmmmm this could be hard.......Take them out !!!

Moondoggie:p
 

0neoffive

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Say Wha ?

I recently installed LED replacement bulbs (lights) for the park/brake lights. They work great and are bright as hell. My only issue is that the front white parking lights activate now when I hit the brakes.

Any idea how to stop this?

OK: I'm sittin' here staring at the wiring diagram and I suspect magic must be happening 'cause there ain't no connections from here to there ??
 

65beam

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lights

duke,
did you buy them from joe parlanti ? if not , you should since he's a tiger owner and does complete kits for tigers. if you have his bulbs and have a problem he will help you out.
 

michael-king

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Duke, its odd the bulb change would cause this issue. I wonder in you had the same issue before but didn't know, which would imply something in the loom.

Try putting the stock bulbs in the front and leave the rear led in, see if fronts still turn on. I have heard of some issues with led replacements with indicator's due to lower power draw... But your issue implies something else.
 

Moondoggie

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Yes, that is a great easy fix but I like the bright lights.

Okay then...I had a similar thing happen when I put LED's in my Superformance Cobra and the fix was changing out the turn signal timer
to a modern solid state one.

Moondoggie
 

HolyCat

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Parking Lights or Turn Signal Lights

Okay then...I had a similar thing happen when I put LED's in my Superformance Cobra and the fix was changing out the turn signal timer
to a modern solid state one.

Moondoggie

Moondoogie - That must have been fun tracking down your problem! If the problem that Duke is experiencing is with his parking lights and not his turn signal lights, not sure changing the flasher unit will help, since it is not connected to the parking lights (unless someone has been rewiring things).

The brake lights get a different feed than the parking lights in the stock wiring. If the brake light bulb and the tail light bulb share a ground and if the ground were poor, could the power from the brake light be going backwards through the tail light bulb(s) and through the front parking light bulb(s) to a good ground? But this would mean that the tail light would also come on when Duke hits the brakes, and I don't think he mentioned that as a symptom. Or do the LED lights work with power only one way, unlike an incandescent bulb which can work regardless of which way it is powered. (A test would be to put incandescent bulbs in the tail light holders and repeat the test. If one or both tail light bulbs light up, Duke should be closer to solving the problem. Another way to test this hypothesis is to simply remove the tail light bulbs and hit the brakes to see if the front parking bulbs light up.)

I think we have seen that quite often electrical problems in our Tigers can be traced back to grounding issues. This is a perplexing issue!
 

Forrest39

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I would think that the brake light signal is somehow bleeding through to the running light circuit. I have seen this before where the two filament bulb looses its ground. I'd suggest disconnecting the running light circuit to the rear bulb and see if that isolates the problem.
Cheers, -Kevin

Edit: I should have read the previous post. David has the right idea.

Before getting fancy, remove one of the lower bulbs at a time and see if you can narrow it down to one side.
 

HolyCat

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Another Vote

Kevin stated it very succinctly. I was trying to explain how it could happen that a bad ground on the stop light could cause the front parking light bulbs to be energized. However, my suggested tests won't work - I had forgotten about that double filament bulb. Kevin suggestion of disconnecting the hot wire to the tail light portion of the bulb is the best test.
 

Warren

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I'm thinking

Most of the bulbs I have seen are early converted brass based bayonet sockets with the glass bulb removed and a LED cobbled into place.

Now going with the above it was even possible to put bulbs into place in a 180 off fashion in the housing which caused similar problems for me on other cars. Possibly operator error, the light mfg surely not you Duke;)
 

TAH_Tiger

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LED Lights

I recently installed LED replacement bulbs (lights) for the park/brake lights. They work great and are bright as hell. My only issue is that the front white parking lights activate now when I hit the brakes.

Any idea how to stop this?

I had a similar problem in that my front white lights were dimmer after installing LED brake lights. Someone suggested changing the polarity by removing one bulb at a time and reinstalling them 180 degrees to make sure the polarity was the same for both bulbs. Haven't had time to try.
 

Duke Mk1a

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The brake lights get a different feed than the parking lights in the stock wiring. If the brake light bulb and the tail light bulb share a ground and if the ground were poor, could the power from the brake light be going backwards through the tail light bulb(s) and through the front parking light bulb(s) to a good ground?


Thats IT! The LED lights have two sets that activate. The outer row only come on with the parking lights. All of the LED lights come on when the brakes are activated so the power is back feeding the parking lights to the front. So a diode installed on the PL wires may fix it????
 
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HolyCat

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Not My First Choice

Thats IT! The LED lights have two sets that activate. The outer row only come on with the parking lights. All of the LED lights come on when the brakes are activated so the power is back feeding the parking lights to the front. So a diode installed on the PL wires may fix it????

Duke,

If it were my car, installing a diode in the parking light circuit would not be my first choice. The PL circuit is being energized when it should not be. Doing a workaround (the diode) might solve the immediate problem, but might cause other problems down the road and make it harder to troubleshoot future electrical problems.

It seems like you just have a poor grounding issue. I would try taking out the combo tail light/brake light bulbs, first one side and then the other and hit the brakes each time. If the front running lights don't light up with one bulb out, I would have found the light with the bad ground. If the running lights light up when either side tail light/brake light bulb pulled (one at a time), then I would suspect both brake light bulbs have a poor ground. I might say screw it and simply clean the grounding on both rear tail lights and not worry which side (if only one) is causing the problem.
 

Forrest39

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I think the idea of the diode would be for testing only to isolate the location of the poor ground. If you left in in the system, the brake light with the problem would not function as the diode would prevent that side from seeing the ground of the front lights.
-Kevin


Duke,

If it were my car, installing a diode in the parking light circuit would not be my first choice. The PL circuit is being energized when it should not be. Doing a workaround (the diode) might solve the immediate problem, but might cause other problems down the road and make it harder to troubleshoot future electrical problems.

It seems like you just have a poor grounding issue. I would try taking out the combo tail light/brake light bulbs, first one side and then the other and hit the brakes each time. If the front running lights don't light up with one bulb out, I would have found the light with the bad ground. If the running lights light up when either side tail light/brake light bulb pulled (one at a time), then I would suspect both brake light bulbs have a poor ground. I might say screw it and simply clean the grounding on both rear tail lights and not worry which side (if only one) is causing the problem.
 

Duke Mk1a

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I do not see this as a ground issue at all. When brakes are activated, 12V go to all of the LED including the PL LED's. 12V then go OUT the PL contact, through the wire to the front PL contacts and then lights them up. Nothing to do with a ground.

This does not happen when the PL are on as they are already activated with 12V in the system.
 

ahetzel

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Does anyone have a good recommended LED replacement for the brake light bulb/lamp? After reading this post I would rather buy a proven product. There are too many LED choices on the market many of with are suspect.
 

TAH_Tiger

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Superbright LED

Does anyone have a good recommended LED replacement for the brake light bulb/lamp? After reading this post I would rather buy a proven product. There are too many LED choices on the market many of with are suspect.

These are the ones I used without issues. I even kept the same flasher. Faster, but not Hyperflash. Just make sure you order RED for red lenses or AMBER for amber lenses. I haven't changed the front to LED (yet)

1156
https://www.superbrightleds.com/cat/tail-brake-turn/filter/Cross_Reference_Number,1156,21,194:

1157
https://www.superbrightleds.com/mor...d-tower-a-type-bay15d-retrofit-car/1915/4479/

Tom
 

Warren

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Daytime

Running Lights are what the fronts look like when on. I use mine a lot when driving in daylight. Been left turned 2x in daylight in a dark colored car ouch.
 
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